Nodal analysis very often is the best method of analysis when a circuit contains op amps, because in electronic circuit the reference node is usually shown as grounded and all other elements connected to the reference node are often shown individually grounded. Thus the nodes are easily identified for the nodal method, but the loops are not so easily visualized. Therefore, a method based on loops, such as the one we consider in the next station, is not so easy to apply. Also, quite often only a relatively few nodal equations are required